I've found a problem about dovecot when installing fresh new iredmail 0.8.3 on centos 64bit today.

1. when setup dovecot, installation alert error module installation because of different version.2. after the installation, i've reboot and dovecot service not running.

this is what i've got if i tried to running dovecot service.doveconf: Error: Module is for different version 2.0.18: /usr/lib64/dovecot/settings/libmanagesieve_login_settings.sodoveconf: Error: Module is for different version 2.0.18: /usr/lib64/dovecot/settings/libmanagesieve_settings.sodoveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf: protocols: Unknown protocol: sieve